US Embassy in France: Never received Packet 4

[Guigui&Arlee 6]

So my fiance sent out packet 3 on January 15 and still has not received packet 4. He does not live far from Paris so it shouldn't take too long to receive mail from the embassy. I recently emailed the embassy asking if they ever received packet 3 and they confirmed that they had and sent out the packet 4 near the end of January. They told me his interview date, which is March 3rd and even the time. He has called the embassy and emailed different people, but no one is being helpful. We have no idea how to get ahold of packet 4 to "officially" set the interview date. If we can't get the packet is there a way we can do everything without it, or is there an important document he needs to bring with him? We are getting a little worried since it is only 3 weeks away and he still needs to pay and set a date for his medical. Thank you for your responses.

[Guigui&Arlee 6]

Also is this the link that is used to set up interview dates? https://ais.usvisa-info.com/en-fr/iv